Zolgensma data including patients with more severe spinal muscular atrophy at baseline further demonstrate therapeutic benefits.- Novartis.

Novartis Gene Therapies announced new interim data from the ongoing Phase III STR1VE-EU clinical trial for Zolgensma (onasemnogene abeparvovec) that demonstrated patients with spinal muscular atrophy (SMA) Type 1 continued to experience significant therapeutic benefit, including event-free survival, rapid and sustained improvement in motor function and motor milestone achievement, including for some patients with more aggressive disease at baseline compared to previous trials.

SMA is a rare, genetic neuromuscular disease caused by a lack of a functional SMN1 gene that results in the progressive and irreversible loss of motor neurons, affecting muscle functions, including breathing, swallowing, and basic movement. These data as of December 31, 2019, and presented during a virtual Clinical Trial Poster Session as part of the World Muscle Society (WMS) 2020 Virtual Congress, support the robust clinical evidence that has demonstrated a consistent, transformative benefit across Zolgensma clinical trials for the treatment of patients with SMA. Phase III STR1VE-EU Data as of December 31, 2019 : STR1VE-EU is designed to evaluate the efficacy and safety of a single, one-time IV infusion of Zolgensma in patients with SMA Type 1 who are less than six months of age at the time of gene therapy, with one or two copies of the SMN2 backup gene and who have bi-allelic SMN1 gene deletion or point mutations. The mean age of dosing was 4.1 months and the mean age at the onset of symptoms was 1.6 months. The mean Children's Hospital of Philadelphia Infant Test of Neuromuscular Disorders (CHOP INTEND) score at baseline was 28. Thirty-one of 33 patients (93.9%) were able to swallow thin liquids, and 10 patients (30.3%) required feeding support at baseline. Nine of thirty patients (27.3%) required ventilatory support at baseline. STR1VE-EU is distinct in its inclusion and exclusion criteria and baseline clinical characteristics of enrolled patients compared with START or STR1VE-US. Specifically, some patients in STR1VE-EU had a more severe disease phenotype at baseline, including lower CHOP-INTEND scores and the need for nutritional and ventilatory support. At last visit before the data cutoff, patients in STR1VE-EU were between 6.9 and 18.6 months of age, and mean duration in the study was 10.6 (1.8–15.4) months. Thirty-one out of 32 (97%) patients in the intent-to-treat (ITT) population survived event-free, including 30 (93.8%) who could have reached 10.5 months of age and 18 (56.3%) who could have reached 13.6 months of age. An event is defined as the need for tracheostomy or the requirement of in at least 6 hours of respiratory assistance per day (via non-invasive ventilatory support) for in at least 14 consecutive days in the absence of an acute reversible illness, excluding peri-operative ventilation. Untreated natural history indicates that only 50% and 25% of babies with SMA Type 1 will survive event-free by the time they reach 10.5 months of age and 13.6 months of age, respectively. Twenty-one patients (65.6%) achieved motor milestones not observed in the natural history of SMA Type 1. This includes six patients (18.8%) who could sit independently for at least 10 seconds (the primary efficacy endpoint), 20 patients (66.7%) who gained head control, eight patients (25%) who were able to roll from back to sides and one patient who could stand with assistance, crawl and walk with assistance. The mean increase in CHOP INTEND from baseline was 5.9 points (n=31) which was observed as early as at one month post-dosing, 10.1 points at 3 months (n=29) post-dosing, and 13.3 points at six months (n=27) post-dosing. Twenty-one children (65.6%) enrolled in STR1VE-EU achieved and maintained a CHOP INTEND score of at least 40 points and 12 children (37.5%) were able to achieve a score of at least 50. According to natural history, untreated patients with SMA Type 1 almost never achieve a CHOP INTEND score of at least 40. The majority (91.7%) of patients who were free of ventilatory support at baseline remained either completely free of ventilatory support or received prophylactic BiPAP support during the study for acute reasons. Two-thirds (66.7%) of patients in the ITT population were able to feed orally without the need for feeding support, an important indicator of stabilization/halting of disease progression. Adverse events: As previously reported, one patient discontinued the study because of a serious adverse event of hypoxic-ischemic brain damage and respiratory distress that resulted in death. Novartis and the investigator considered the events and death to be unrelated to treatment with Zolgensma based on autopsy findings. Thirty-two of 33 patients were reported to have at least one adverse event (AE), of which six patients experienced serious adverse events that were considered by the investigator to be related to Zolgensma. Liver transaminase elevations, some of which were reported as adverse events, were experienced by 29 of 33 patients (87.9%), but all resolved with the use of prednisolone. Four patients had reported decreases in platelet counts less than 75,000, three of which were isolated laboratory abnormalities without adverse events reported. Overall, no new safety signals have been identified and the reported adverse events are consistent with the cumulative safety profile with Zolgensma.